Sleep 101 for Parents How Sleep Works in Your Kid's Brain Two children are sitting under my exam table fighting over an iPad featuring a virtual pet (named Lady Gaga) who requires some type of care or it will die. There is a heated disagreement as to whether it should be fed. An older girl is reading Junie B. Jones Has a Monster Under Her Bed, and seated next to her is Mom, who is nursing child number four. Mom begins: "I thought I had been given the worst sleeper in the world when Emma was born, but Gabe is going to take that title from her, I think." Emma peers up from her book, looks at me with an ashamed expression, and resumes reading. Mom continues to fuss with Gabe, who truly seems to be smiling as he refuses to engage with nursing. Despite his age, it looks like he's trying to get a look at the iPad instead. I listen and jot notes for the next twenty minutes as Mom describes a chaotic home that reminds me of the Herdmans from that book The Best Christmas Pageant Ever. Throughout the conversation about inconsistent sleep schedules, napping disasters, and a house that always seems to have at least one child awake and in some kind of need, Mom does not verbally leave much to the imagination when it comes to how she feels about her kids' sleep. "They have no schedule, just like their father . . . and he wants to have another!" There is nothing more magical than watching a baby sleep. The sight of an infant sleeping quietly, curled into roughly the position he was in when he was inside his mother's womb just days ago, is instantly soothing. Watching the nuanced changes in his facial expression, the sudden muscle twitches, and subtle movements of primitive reflexes quickly reveals to the observer that there is a wealth of changes happening inside his growing brain. As every mother or father sees their newborn sleep for the first time, a dynamic process, hidden from view, is forming the essence of who that child will be. Prenatal Development of Sleep As you can imagine, studying sleep in a preterm fetus is hard since it is deeply tucked away inside a lovely woman who thinks her partner is doing a lousy job rubbing her feet. Because of the technical difficulty in getting a Fitbit around an unborn baby's wrist, it is not easy to gather information on the subject. Most parents know that their baby's heart begins to beat around day twenty-two of gestation. Looking for a relatively simple heartbeat and measuring something as complicated as the genesis of sleeping behaviors are different beasts. Consequently, fetal sleep is a bit of a mystery to sleep researchers. Much of the data we have about the subject comes from studying animals, mainly primates. Dr. Dan Rurak, professor emeritus of maternal fetal medicine at the University of British Columbia, noted in primate studies that sleep seems to begin at some point during the second half of gestation. In humans, as the neurological development of babies is absolutely exploding, they begin organizing their sleep into distinct patterns sometime near the beginning of the third trimester, as by then the newly formed neural network has matured to the level capable of producing this complicated process. For perhaps the first time, sleep serves as a window into the functioning of the nervous system. This reflection will be observed throughout a child's lifetime. Neurologists are fascinated by development-the maturation of the brain, the development of neurotransmitter systems, and the behaviors that flow from them. Let's back up a little bit and examine the neurological development of a growing fetus. By week six, nerve cells begin to appear, and soon after, the brain is churning out 250,000 new cells every minute and organizing them into an intricate interconnected network. As this massive and complex system is being built, primitive rumblings of electrical activity begin to appear. Like the network itself, the early signs of sleep/wake patterns begin to emerge, and like the system as a whole, these rudimentary beginnings of sleep rapidly develop. In humans, it is thought that genuine sleep starts sometime around week twenty-seven, the beginning of the third trimester. As this neurological network is put into place and the foundation for sleep is laid, primitive shifts of the arousal state are evident for the first time. The fetus is quiet. The fetus is kicking. For many mothers, this change is the first time this unseen, unknown life-form inside of their womb becomes real. He is in there, and he has a rhythm just like the rest of the world's inhabitants. Look who's up and busy at 3:45 a.m.! We can see patterns of sleep and wakefulness begin to appear by halfway through the pregnancy. Usually these patterns are referred to as quiet sleep, active sleep, quiet wake, and active wake (these terms are used even though the baby is not truly ever awake). Early on, these behaviors are limited and disorganized, but as time passes, they become far more orderly and predictable. Many mothers begin to appreciate these patterns in their unborn children. While poorly studied in humans, a 2011 study on mice pups by Dr. Douglas McMahon, a pioneer in the field of chronobiology and vision, indicated that a mother's activity during the day and her circadian rhythm can influence the sleep/wake patterns of her unborn child. When it comes to the struggles of new parents, few are as daunting as getting a new baby to sleep. While reading some of the countless books dedicated to sleep in babies, keep in mind that "baby sleep training" (whatever that is) is happening even as a mother sits down to read a book with a baby in her belly. Mom's sleep schedule, activity level and timing, and her mealtimes may culminate in helping her unborn child begin to entrain patterns of wakefulness and rest. While research on this topic is sparse, it does exist. For example, a study in 2002 by French researchers Jean-Pierre Lecanuet and Anne-Yvonne Jacquet showed fetal heart rate response to maternal rocking (but interestingly, not gliding). Two years later, Yukari Nakajima noted a similar response with driving during pregnancy. Studies from the 1980s demonstrate relationships between maternal heart rate during sleep and that of the fetus. As you can imagine, the study of the relationship between the behavior of a mother and the sleep of her unborn child is difficult and invasive, but there is evidence that the fetus has the ability to take in information and for that information to influence behavior, including the behavior of a child's sleep. Fear not, the study and understanding of sleep will become much more accessible once the baby is born. If you happen to be pregnant and reading this book, think about the activities in which you engage every day. Sitting quietly scrolling on your phone or working at your desk, driving, exercising, eating, sleeping, and, of course, rocking. Try to organize your day in such a way that these activities are happening at specific times every day. In other words, they are scheduled. For example: Up at 7:00 a.m. Breakfast at 7:30 a.m. Walk the dog Quietly work for a few hours Lunch at 12:30 p.m. Read the paper and quietly rock for thirty minutes More work Cycle class Dinner Quiet evening and bed at 10:00 p.m. Keep a consistent schedule full of cues so your developing baby can set the stage for better sleep well before they enter the world! Excerpted from The Rested Child: Why Your Tired, Wired, or Irritable Child May Have a Sleep Disorder--And How to Help by W. Chris Winter All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.
